Float Level Switches

How Float Level Switches Work

Float level switches—sometimes called float level controls—rely on the classic buoyancy principle: the upward force on an object equals the weight of the liquid it displaces. In practice, a precision-balanced stainless-steel or alloy float rides on the liquid surface and moves exactly as the liquid level rises or falls.
Inside every AMETEK LMS float switch, that motion pulls a magnetic sleeve through a non-magnetic barrier tube and into (or out of) the field of a switch-actuating magnet, producing a clean, snap-action change of state.
The result is a rugged, drift-free signal for high-level alarms, low-level cut-outs, pump control, or interface detection—even in demanding services up to 1000 °F (538 °C), 3750 psig (258 bar), and specific gravities down to 0.32

Why Choose AMETEK LMS for Float Level Switches

• Engineer-to-Engineer Collaboration - Our level-measurement specialists review your P&ID, process fluid data, and environmental conditions to specify the exact float geometry, stem length, mounting style, and switch type your application needs - no over-or under-engineering.
• Application-Proven Reliability – Field data show AMETEK LMS float switches exceeding 10-year mean-time-between-failure (MTBF) in high-cycle refinery and power-plant service. Fewer interventions mean lower total cost of ownership.
• Built for Harsh Service – Proprietary welding, full-penetration radiography, and 100 % helium leak testing ensure each switch survives extreme temperature, pressure, and corrosion without recalibration.
• Lifecycle Support – From start-up assistance and spare-parts programs to on-site health checks, our global service team keeps your measurement loop running.
• Industry Compliance – FM, CSA, ATEX/IECEx, PED, CRN, and SIL options help you meet safety-integrity and regional code requirements without extra paperwork.

Typical Float Level Configurations